Population Biology

P. Aurelia grown alone, cells, mL P. caudatum grown alone , cells, mL P. Aurelia grown in mixed culture, cells/mL P. caudatum grown in mixed culture, cells/mL

Day 0 2 2 2 2

Day 2 10 10 6 10

Day 4 52 28 32 20

Day 6 84 52 64 18

Day 8 94 58 80 16

Day 10 98 56 88 8

Day 12 98 56 92 2

Day 14 100 58 98 0

Day 16 98 60 92 0

Journal Questions

1. Make a hypothesis about how you think the two species of Paramecium will grow alone and how they will grow when they are grown together. (Make sure you understand what a hypothesis is before you address this!)

My hypothesis for the two species of Paramecium is that they will grow better alone then together. Also when they grow together, it is likely that one will kill off the other

2. Explain how you tested your hypothesis. (Give details of how you conducted your experiment. Consider this the "Methods" section of a lab report.)

To test my hypothesis I used the experimental control technique .Three test tubes had rice in them. The differing condition was that one test had the Paramecium caudatum. One test tube had the Paramecium aurelia. One test tube had both in it. Then every two day a sample from each test tube was observed to see what varied or what remains the same.

3. On what day did the Paramecium caudatum population reach the carrying capacity of the environment when it was grown alone? How do you know?

When grown alone the Paramecium caudatum population reach the carrying capacity of the environment on the 14th day. This fact is known because on the 16th day the population started decreasing.

4. On what day did the Paramecium aurelia population reach the carrying capacity of the environment? How do you know?

When grown alone the Paramecium aurelia population reach the carrying capacity of the environment on the 14th day. This fact is known because on the 16th day the population started decreasing

5. Explain the differences in the population growth patterns of the two Paramecium species. What does this tell you about how Paramecium aurelia uses available resources?

When grown alone the Paramecium aurelia population grew quicker than the Paramecium caudatum population. This shows that the Paramecium aurelia was able to use all available resources.

6. Describe what happened when the Paramecium populations were mixed in the same test tube. Do the results support the principle of competitive exclusion?

When the two populations were mixed together,